[1] In this action for personal injury the pursuer, MD, sues his former employers, AMEC Group Limited, for chronic Post Traumatic Stress Disorder (“PTSD”) said to have been suffered as a result, and in the aftermath, of a fire on Absorber Unit 3 (“Absorber 3” or “the Absorber” as the context requires) at the Longannet Power Station on 23 March 2009. The pursuer did not sustain any physical injury.

[2] On the pleadings, the pursuer’s positive case is narrowly cast. The only factual averments going to fault assert that there was only one exit from the roof of the Absorber at the material time. As will become clear, at the proof the pursuer sought to lead evidence in support of a number of additional grounds of fault and for which, the defenders contended, there was no record.

[3] The pursuer, aged 59 at the date of the proof, had worked as a labourer since about 1972. He had worked mostly on construction sites or in dockyards in Fife. He has previously worked for AMEC on several occasions. Prior to the date of the fire on 23 March 2009, the pursuer had been working for AMEC on the Longannet Power Station site continuously since about 2006 as a labourer. The pursuer’s recollection is that he commenced on site in June 2006.

[4] The pursuer’s main job with AMEC had been to work with the safety team and on environmental matters. This was at ground level. He assisted in the labelling of skips used for disposal of certain forms of materials (eg wood, metal etc) and he would clean up oil spills on site. He was also a labourer and assisted others as “mate”, a role he was engaged in on the day of the fire.

Absorber Unit 3[5] The pursuer’s case on record concerns an asserted failure on the part of the defenders to have sufficient means of egress from the Absorber structure on which the pursuer was working on the afternoon of 23 March 2009. In order to understand where the pursuer was working and what means of egress were available to him, it is first necessary to explain the structure on which the pursuer and others were working on the day of the fire.

[6] As a consequence of the fire, Absorber number 3 was demolished and rebuilt. A considerable amount of time was taken up at the proof with evidence, and objections to evidence, to try to establish the features of Absorber number 3 as they were at the material time, and in particular, the fixed and any temporary horizontal walkways, scaffolding and the point or (if more than one) points of vertical access on and off the structure. There were in excess of twenty external photographs taken of the structure at some point during the fire on 23 March 2009. Only three of these were subject to agreement in the joint minute. In addition, there were some isometric drawings (to which objection was taken), and one or two more stylised overhead figures (to which objection was also taken).

[7] The efficient or clear presentation of the evidence on this significant aspect of the case was bedevilled by the following:

(i) the lack of a key to the colours used for figures 6 and 6A of the Report of Mr Sylvester-Evans (No 7/62 of process) providing an overhead view of certain features of the structure;

(ii) the failure to provide the opposing party with colour copies of those figures;

(iii) the failure to provide the opposing party with copies of those isometric drawings containing an architectural legend (with descriptions, scale and other data), (Nos 7/19 and 7/22 of process); and

(iv) the failure to provide any drawing or plan with simple marked reference points to assist the examiner in posing concise questions, or to assist the witness or the court in understanding the questions posed, about the physical features of what is a complex structure. An attempt to provide the latter was finally lodged, at the behest of the court, as 7/68 of process. Unfortunately, the pursuer did not have the benefit of this for the purpose of his evidence.

Absorber Unit 3: Its Purpose [8] As reliance is placed on features of the Absorber to explain why certain desiderated fire precaution steps or systems would not be reasonably practicable, it is necessary to describe its proposed operation and, so far as possible on the evidence available, its external physical features at the material time.

[9] Absorber 3 was one of three such Absorber units, described as flue gas desulpherisation units (or FGDs), being constructed at the Longannet Power Station. In brief, the purpose of an Absorber was to remove or reduce the amount of sulphur in the gas emissions from Longannet Power Station, as part of an initiative to generate cleaner or, at least, less pollutant energy. The process relied on the chemical reaction of combining alkaline seawater with acidic flue gases with the intended result of producing pH neutral emissions.

[10] The means by which this was done involved the construction of a large concrete box structure in the immediate vicinity, just to the south, of the Longannet Power Station. In operation this would be sealed and was referred to in evidence as “the chamber”. As designed, there was only one access door to the chamber, on the south face, and situated relatively low down on that face. The Absorber was comprised essentially of this chamber, together with the external features on that structure.

[11] Gas emissions from the Longannet Power Station were pumped into the sealed chamber of the Absorber, through an inlet duct, which fed the gases in near the bottom of the concrete part of the chamber. The gases would then rise up and, once treated, would be removed via the outlet duct. The flue gasses would then be directed to the chimney, which was west of the Absorber structure. Meantime, large volumes of seawater were pumped to the top of the Absorber. Through a series of pipes with branched arms or splays, the seawater would be sprayed onto what was described as “packing material” to wet it. The packing material consisted of polypropylene, a flammable material. The polypropylene packing material was structured in such a way so as to maximise the surface area which could be wetted with the seawater. As the gases rose up through this wet material, the desired chemical reaction would take place. The seawater flowing down through this packing material would then be pumped away. In normal operation, the chamber would effectively be a sealed concrete box filled with sea water and to which no worker would require to have internal access.

[12] Situated above the concrete chamber of the Absorber was the gas heat exchanger (“GGH”). The GGH was designed to extract heat from the flue gases as they entered the Absorber. It was cylindrical structure of about 18 metres in diameter and, when in operation, rotated on a central shaft. The circular cover of this, referred to as the flange, was situated in the sloping roof (described further below).

[13] At all material times, the movements of the pursuer and others was on the external parts of the Absorber, that is, the parts exposed to a greater or lesser extent to the outside air. I turn to describe those external features in more detail.

Absorber Unit 3: External Features in Outline[14] The Absorber was, externally, a complex structure with a series of fixed horizontal walkways circumnavigating most of the structure. In addition, at the material time, there was a great deal of scaffolding around some of the Absorber’s external faces. The two large inlet and outlet ducts are best described as each forming a rounded “M” at the point where they surmounted the concrete chamber of the Absorber, oriented on a north-south axis, and with the south ends of each fixed to the top of the large concrete box structure that comprised the enclosed chamber of the Absorber. The top surface of the two ducts was higher than 29 metres. The two ducts were bisected on an east-west axis by expansion joists. The outlet duct was to the west of the inlet duct. The inlet and outlet ducts were not simple “M” structures, running on north-south axis, as I have already described. Each duct also had a section running perpendicular to the “M”, with the east-west running section of the outlet duct running beyond the Absorber, to the west, into the chimney. The east-west portion of the inlet duct protruded beyond the Absorber at the other side, at its north-east most corner. This part of the inlet duct is only relevant as, on the evidence of Mr Sylvester-Evans, if one reached the north side of that part of the inlet duct, the solid feature of that duct afforded sufficient protection from the fire that that area could be regarded as a place of safety (for fire safety purposes). This is the area shown between letters G and H of No 7/68.

Absorber Unit 3: The North Passageway between the Inlet and Outlet Ducts[15] The structure of the inlet and outlet ducts representing two “M”s on a north-south axis were parallel to each other, but not abutting, so that, at a certain level, there was a walkway between the two ducts, again running on a north-south axis, heading to the north away from the Absorber. This walkway is signified by the yellow passageway between letters “E” and “F” on 7/68. Apart from the sloping roof I will describe in a moment, the only accessible parts of the Absorber at any height was by a series of external horizontal walkways fitted to the structure of the Absorber at various points. I describe these in more detail below.

Absorber Unit 3: The Sloping Roof[16] The west part of Absorber 3 had a gently sloping roof, sloping down from the central part of the Absorber to the western face of the Absorber unit. The purpose of the slope was to facilitate the direction of the gas within the chamber as it rose towards the outlet duct. As will be seen, the pursuer was rescued from the sloping roof. The sloping roof at its highest, that is where it joined the main part of the concrete box structure of the Absorber, was a little below 21 metres above ground level. The circular top or flange of the GGH was also situated on the sloping roof.

Absorber Unit 3: The Three Fixed External Horizontal Walkways[17] Access to certain parts of the external structure of the Absorber was via a series of three fixed horizontal walkways. In broad terms, there was no dispute on the evidence that there were three fixed horizontal walkways, at the heights, respectively, of 21, 23 and 29 metres above ground level and which were fixed along the length (or most of the length) of the west, south and east faces. The part of the walkway designed to be walked on was comprised of “Kennedy” grating: thick diamond-shaped metal grating which readily allowed air to flow through and around it. An example of this may be seen at photos 5 and 7 of No 7/62. There was no clear evidence as to the north face of the Absorber at the point it joined to the power station. The inlet and outlet ducts were also situated on this side. In any event, there were no photographs, drawings or other plans or figures produced or spoken to in evidence showing the north face of the Absorber at the material time.

Absorber Unit 3: The Horizontal Walkways along the East and North Faces
[18] If one travelled from the southeast corner of the structure, along its east face, heading north, the ducting interrupted the two lower walkways (ie those at 21 and 27 metres above ground level) about half-way along the east face. So far as the evidence disclosed, the highest walkway (at 29 metres) was able to continue along the whole east face of the Absorber, i.e. it was able to continue as it was just above the ducting that blocked the two lower walkways from proceeding in a straight line along the east face. While the evidence was not entirely clear, it would appear that if one started from the south east corner of either of the two lower walkways and headed along the east face toward the north, the inlet ducting that came in at a right angle as it joined the east face would block any further progress along those two lower walkways. Instead, one would turn left and would then be heading west on an east to west axis.

Absorber Unit 3: The Valley as an East-West Route under the Ducts at the Level of the Two Lower Walkways[19] At this point, while still external to the Absorber chamber, one would be surrounded by features of the Absorber structure. In particular, the two lower walkways passed through the underside of the south-most arches of the two “M”s formed, respectively, by the inlet and outlet ducts. There was ducting to the right, or north side of each of these lower walkways. This passageway running on an east-west axis along the north side of the Absorber, and semi-enclosed by the south-most of the arches of the inlet and outlet ducts, was known as the “valley”. It is depicted in photo number 8 of No 6/15 of process. At the material time, the two lower walkways passed through the valley. By reason of the ducts arching overhead, the valley was not open to the elements above. However, it was open to the outside at both its west and east ends. While in one sense it was tunnel-like, there was a significant degree of clearance above the walkways. This part of the Absorber may be described as semi-enclosed. (The physical characterisation is relevant to the calculation of safe travel distances, as will be discussed in the context of the expert evidence, below.)

Absorber Unit 3: The East-West Route under the Ducts at the 29 Metre Level[20] From the lowest walkway one could look up through the open “Kennedy” grating of the middle walkway. At the point where the highest walkway was on an east-west axis it was not above the other two walkways. By reason of the fact that the highest walkway was above the level of the inlet duct feeding into the east side of the Absorber structure, it was possible on the highest walkway to travel further along the east face of the Absorber structure than was possible to do on the two lower walkways.

Absorber Unit 3: The Southeast Stair[21] It was not disputed that the main vertical access and egress from ground level to the walkway at the 21 metre level was the southeast stair. This was a permanent metal stair fixed to the south-most part of the east face of the Absorber. While one of the isometric drawings (No 7/18 of process) bears to show a further external stair from ground level up to the 21 metre walkway, it was accepted that this was never in fact built - either on the Absorber at the material time or on the rebuilt Absorber. It was assumed, rather than a matter of clear evidence, that at some point on the structure one could access the 27 metre walkway via a further single stair from the 21 metre level; and that the 29 metre level could also be accessed from a stair leading up from the 27 metre level. There was no clear evidence as to whether there was more than one stair giving access between the 21 and 27 metre levels, or between the 27 and 29 metre levels.

Absorber Unit 3: Circumnavigation of the Outside of the Absorber via the Walkways at 21 and 27 Metre Levels[22] Parties proceeded on the basis that for someone at the northwest corner of one of the two lower walkways, it was possible to access the southeast corner of the Absorber unit (and hence the southeast stair) either:

(i) by going east along the north face, before turning right (or south) and heading along the east face (“route (i)”), or

(ii) by going south along the west face, before turning left and heading east along the south face (“route (ii)”).

If one took either of these routes along the fixed walkway at the 21 metre level, one would arrive at the top of the southeast stair and, using those stairs, could reach ground level. If one went via route (i), then part of this journey entailed going through the semi-enclosed “valley”, described in paragraph [19] above. If one used route (ii), the walkway at all points was external to the structure. While from the northwest corner, either of these two ways of going led to the same place - namely the southeast corner and the southeast stair, it appeared to be a common ground between the experts that for the purposes of escape this constituted two separate routes albeit with a shared end part.

[23] While the permanent features and walkways of the Absorber have been described, there were also temporary structures or scaffolding in place on and around the Absorber.

Absorber Unit 3: The “Dance Floor”[24] There was some limited evidence that there was a large scaffold platform to the north of the Absorber. By reason of its size, it was given the name “the dance floor”. So far as the evidence went, while this provided a space to retreat to below the level of the fire, there was no evidence that one could directly access the ground level from the dance floor.

Absorber Unit 3: The Stage at which the Construction had Reached[25] The construction of the Absorber was essentially complete, although there were snagging works ongoing such as that on which the pursuer and John Robinson were engaged. The pursuer himself commented that most of the scaffolding had been taken down. The Absorber was in the process of being prepared for commissioning, which was imminent. On the morning of 23 March 2009, one of the pumps – situated about a kilometre away - had been activated and very large quantities of seawater pumped into the Absorber chamber.

Scope of the Pursuer’s Proof on Record[26] It must be noted that in the first few days of this proof, a considerable amount of time was taken up with hearing objections. From the Report of the Commissioner, it would appear that this was also the position in respect of one of the pursuer’s experts, Mr MacGillivray, whose evidence was taken on commission a week before the proof. (Accompanying the Commissioner’s Report there are 12 papers apart containing the objected to lines of evidence.) Throughout the proof, the defenders took objection to lines of evidence that the pursuer sought to elicit, essentially on the basis that there was no Record. The lines of evidence objected to include the following: an asserted lack of certain safety provisions on the Absorber, such as deluge systems, fire escape signage, fire alarms, personal safety equipment, personal safety instruction for or training of the pursuer about what to do (or which exits to take) in an emergency, and so on, on the basis that there was no Record. Objection on the same basis was also taken to lines of enquiry directed to the cause of the fire, and to criticisms of the defenders’ risk assessments. The pursuer’s reply in short, was that this was a personal injury action and that, consistent with the latitude of pleading associated with that form of procedure, the pursuer’s pleadings sufficed. The arguments on these objections to all of these lines of evidence were broadly the same. It will suffice, therefore, to address these collectively and to collate parties’ arguments, rather than to set out each of the many objections individually.

The Parties’ Pleadings

[27] Before noting the parties’ arguments in detail, it is appropriate to set out the parties’ pleadings. The pursuer’s positive case was in short compass and to the effect that there was only one route off the Absorber. The only averments of fact capable of supporting a case of fault were as follows:

“Prior to the fire there had been exits at a number sides of the building. At the time of the fire the only way to exit the roof was to use the stairs at the east side of the building. It was impossible to use those stairs to exit the roof due to smoke and fire.”

The pursuer’s legal averments of fault, reproduced in full, are as follows:

“STAT 6. The said claim is based on the defenders breach of the statutory duties imposed upon them by section 53 of the Fire (Scotland) Act 2005, regulations 4, 5, 6 and 7 of The Work at Height Regulations 2005, regulations 4 and 5 of the Provision and Use of Work Equipment Regulations 1998, regulation 3 of the Management of Health and Safety at Work Regulations 1999, and regulations 13, 26, 38, 39, 40 and 41 of the Construction (Design and Management) Regulations 2007. The defenders’ averments in answer are denied except insofar as coinciding herewith.”

[28] In submissions at the end of the proof, the pursuer’s senior counsel abandoned any case based on the Work at Height Regulations 2005 and the Provision and Use of Work Equipment Regulations 1998. He maintained his case based on:

(1) section 53 of the Fire (Scotland) Act 2005 (“the Fire Act 2005”)

(2) regulation 3 of the Management of Health and Safety at Work Regulations 1999 (“the Management Regulations 1999”), and

[29] The totality of the factual averments made by the pursuer were as follows:

“STAT. 4 On or about the 23rd of March 2009 the pursuer was engaged in the course of his employment with the defenders. The pursuer was working within the defenders’ site at Longannet Power Station, Alloa, Clackmannanshire FK10 4AA. The said site was a construction site. The defenders were the principal contractors on the site. He was working on a roof of a building that the pursuer knew as, ‘The Absorber’. The building was very large. The roof had scaffolding to access it. The scaffolding was approximately 28 metres high. Whilst on the roof the pursuer noticed smoke coming from the building beneath him. A co-worker shouted to the pursuer, “Mel, there is a fire, get down.” The pursuer went to the south end of the scaffold on the west side of the building, but he couldn’t get down that way. He then went to the north side, but couldn’t see through the smoke. The pursuer was agitated and afraid. He considered running through the smoke, but decided against it. He then went to where the roof was at its lowest, about 20 metres high at this point. He shouted on a co-worker to get a cherry picker to rescue him. The fire seemed to get worse. The pursuer thought that he would die. Whilst waiting on the cherry picker one of his colleagues shouted on him to jump. Whilst waiting on rescue the pursuer noticed that the fire was making a loud roaring noise. He saw flames. The pursuer became concerned that the building would explode. After some time rescue personnel from OPUS Industrial Services Limited attended at the scene and managed to get to the pursuer. As the area was thick with black smoke they attached a 15-minute oxygen canister to the pursuer’s face. They were about to lead him back through the smoke to the scaffold when a cherry picker arrived and rescued the pursuer. As a result of the said accident the pursuer suffered loss, injury and damage. Prior to the fire there had been exits at a number of sides to the building. At the time of the fire the only way to exit the roof was to use stairs at the east side of the building. It was impossible to use those stairs to exit the roof due to the smoke and fire. The defenders’ averments in answer are denied except insofar as coinciding herewith. Explained and averred that after the accident a Panel of Inquiry was set up to examine the causes of the accident and to make recommendations to avoid a recurrence. Membership of the Panel consisted of […..] The Panel produced an interim report dated the 16th of June 2009 which noted that, ‘Access to and from the absorber is via a single stairway on the east side of the absorber.’. It concluded, inter alia, ‘A thorough review of the access/egress arrangements to/from the FGD absorbers is required to be undertaken to ensure that staff have a clear route to ground from any level in the event of an evacuation.’” (Emphasis added.)

[30] After making certain admissions, the defenders’ response (insofar as it concerned the number and means of egress from the Absorber) to this part of the pursuer’s case was as follows:

“Admitted that after the accident a Panel of Inquiry was set up under explanation that that was done to investigate the cause of the fire (as distinct from “the accident” which might refer to the fire or to the pursuer’s circumstances) and to make recommendations to prevent the recurrence of a similar incident. The interim report is referred to for its terms, under explanation that there were in fact multiple routes of egress from the absorber as condescended upon below. The details of the pursuer’s movements and thought processes are not known and not admitted. Quoad ultra denied. The pursuer is called upon to aver which level of the Absorber he was on when he first noticed smoke. He is called upon to aver why he did not exit the Absorber by the stairway in the northwest corner, or by the scaffold to the north of the building, in light of his averment